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iOS Object-Oriented Swift Class Inheritance Creating a Subclass

Sam Kearney
Sam Kearney
2,058 Points
Posted by Sam Kearney
Sam Kearney
2,058 Points

Class Inheritance Code Challenge Help

I think the initialiser is what's throwing it off, but I'm not sure what's wrong. Anyone see the issue?

Thanks

objects.swift 
class Vehicle {
  var numberOfDoors: Int
  var numberOfWheels: Int

  init(withDoors doors: Int, andWheels wheels: Int) {
      self.numberOfDoors = doors
      self.numberOfWheels = wheels
  }
}

// Enter your code below

class Car: Vehicle {
  let numberOfSeats: Int = 4

  init(withSeats seats: Int) {
    self.numberOfSeats = seats
  }
}

let someCar = Car(withSeats: 5)

1 Answer

Dylan Glover
Dylan Glover
2,537 Points

Hey Sam, Got this answer from an older question on this challenge, but it passes and seems to explain pretty well. Looks like you were really close!

class Vehicle {
    var numberOfDoors: Int
    var numberOfWheels: Int

    init(withDoors doors: Int, andWheels wheels: Int) {
        self.numberOfDoors = doors
        self.numberOfWheels = wheels
    }
}

// Enter your code below

class Car: Vehicle {

    var numberOfSeats: Int = 4

    init(numbersOfSeats: Int) {

       // We first give values to "numberOfSeats
        self.numberOfSeats = numbersOfSeats

      // Then we call super init
        super.init(withDoors: 2, andWheels: 4)
    }
}

let someCar = Car(numbersOfSeats: 2)

Hope this helps!

Dylan

Sam Kearney
Sam Kearney
2,058 Points
Sam Kearney
Sam Kearney
2,058 Points

I understand it much better now. Thank you!

Dan K
Dan K
10,689 Points

why don't you add "doors" and "wheels" when you call super init?